| Felix Nink at Robert Bosch GmbH Packaging Technologies examines trends and novel solutions in encapsulating liquid products
Production of liquid filled capsules has become a much soughtafter solution in the pharmaceutical industry. With various developments and innovations, liquid filling technology is increasingly considered as a viable alternative to hard capsule filling. This trend in providing users with various filling process alternatives has evolved from crucial variables and characteristics of the products on the market. To this end, high performance filling machines for liquid encapsulation have been taking the lead, offering a more flexible, cost-effective, and safer production process.
PHARMACEUTICAL ASPECTS OF LIQUID FILLING
Until recently, liquid filled capsules were not a first choice as a formulation for clinical trials or new approvals; this was due to the various sealing or handling problems that have been encountered in the past. Unlike the standard powder capsules, liquid-filled capsule shells are in closer contact, with the risk of causing increased substance migration or partitioning.
Over time, encapsulation technology has improved and advanced, and users have seen several advantages in formulating liquid and semi-solid fillings for some applications in hard gelatin capsules. Drug actives with certain characteristics, such as a low melting point, low dose and critical stability, are difficult to develop in a solid oral dosage; the formulation as liquid or semi-solid fillings in gelatin capsules has proved to be a far better alternative.
Drug substances with a low melting point might liquefy or becoming ‘sticky’ at room temperature. In order to maintain flow properties that allow processing in filling machines, up to 50 per cent of excipients have to be added. In case of high doses, this might lead to quantities no longer suitable for formulation as a single dosage form. |
